Chain grate for furnaces



Patented May 14, 1929.

vUNITED STATES 1,713,322 PATENT ori-fica.,

ALFRED WILLIAM- KENNIS, o'F 1.1mm, HULTQN, BOLTON, ENGLAND.

CHAIN @RATE FOR EURNACES.

Application Med-January 26, 1927, Serial N'o. 163,758,7and inV Great Britain January 2l, 1928;

' This invention relates tor improvements in movingcchaingrates for steam generator and other furnaces and has particular reference toV thaty type of grate in which a plurality of links or grate bars are arranged on pivotal rods so as to form an endless chain for carrying the fuel through a furnace, my general object being to provide a chain grate in which a greater vpercentage of air space to grate,v having nely-distributed effective air spaces, than is common with chain grates heretofore in use, can bez utilized for combustion; such air spaces being arranged to provide for the efficient andV satisfactory burning of low grade fuels, including fuels low in. volatile matter such asl coke breeze, coke ballast, anthracite and anthracite fuels. My principal object is to provide air spaces in the grate bars or links so arranged that -a portion of the air required for combustion may be projected towards the incoming fuel to assist the lighting up of the fire bed, or alternatively, if desired, a portion of the air may be projected rearwardly of the furnace depending upon the manner in which such links or grate bars,I are arranged on their pivotal rods.

This invention consists in the novel construction and combination of the parts hereinafter fully described and claimed.

In the drawings,

Fig. 1 is a side elevation of a portion of a chain ,grate showing one form of links composing the grate in accordance with the present invention.

Fig. 2 is a part plan and part section of a fragment yof the grate.

Fig. 3 is a transverse section of two of the links on line 3 3 of Fig. l.

Fig. 4 is a side elevation of a single link of those shown in-Fig. 1.

The present invention consists in providing the links or bars a with inclined air channels b arranged on the side of the links. These channels are inclined forwardly towards the front of the grate, the .grate travelling in the direction of the arrow indicated in Fig. l. These air channels are inclined at a slight angle to the longitudinal axis of the link, the channels being such that the angle of inclination is at a lesser angle than the normal angle of repose of the fuel to be burnt on the grate. On each link one inclined air channel b is situated directly 'above and around one pivotal centre c of the link as considered when the grate ismovinclined air ychannelb forms with thenext succeedingl link in the rear, a similar shaped airr channel. The air channelsl are so disposed that `the riddlings or ash material king along the upperstretch whilst another abo'uts to the respective pivotal centres o whilst each channel. similarly is provided with a continuation e., The air channels'b I1-Land their continuations e e" respectively preferably increase in width from the points `of air discharge to the points g' at which air enters them, or giving a jet effecten discharge and a widerv lower portion admitting or ri'ddling or ash ydischarging readily at the points previously referred to.

No'inclined air channel is employed intermediate of the two pivotal centres c of the link as in the case of a prior construction of mine.

In addition to the inclined air channels Z) previously described I may employ at the upper adjacent sides of the links comparatively narrow air spaces g1 for the supply of additional air for combustion, such spaces being formed by reducing the width of the link atone or both sides at L to less than thatat the hub portions i.

In accordance with a furtherfeature of my invention the surfaces of the link a! at the sides of such narrow air spaces g1 may be provided with a plurality of comparatively smallgrooves j to facilitate the passage of air. These ,grooves may be inclined preferably in a direction similar to the angle or direction of the neighbouring .inclined air channels b at the side of the grate bars or links.

In the preferred construction the two inclined air ports b ofthe link or grate bar a are situated on one side only as shown in the drawing so that the opposite side al of the pivots arranged parallel to each other, .a

series of grate links mounted on said pivots, hub portions on said linksl which are wider than the remaining portions of said'links to provide longitudinal air passages between the sides of the upper portions of 'laterally adjacent links, a tapering air inlet channel on the side of each of said links which eX- tends around the rear side of the hub portion from the bottoni to .the top thereof and thence upwardly and forwardly to the tops of the links in a ydirection towards the incoming fuel on the grate and a second air channel similarly inclined towards the incoming fuel on the grate, the second channel being formed and-shapedusimilarly to the first channel bythe co-operation of each link with `its next succeeding link in the rear thereof. i

3; A chain grate including a number of pivots arranged parallel to each other, a series of grate linksmounted on said pivots, hub portions on said links which are wider than the remaining portion of said links to provide longitudinal air passages between the sides of the upper portions of laterally adjacent links, upwardly and forwardly inclined grooves formed on the sides of said upper portions of the links, a tapering air inlet channel on the side ofgeach' of said links which extend around the rear side of the hub portion from the bottom to the top thereof and thence upwardly and forwardly to the tops of the links in a direction towards the incoming fuel on the grate and a second air channel similarly inclined towards the incoming fuel on the grate, the second channel being formed and shaped similar to the first channel 'bythe co-operation of each link with its nextl succeeding link in the rear thereof.

In testimony whereof I have hereunto set my'hand. y

ALFRED VLLIAM BENNIS. 

